Washing machine



W. BRETTER WASHING MACHINE Nov. 24, 1953 3 Sheets-Sheet 1 Filed Aug. 12,1952 WALTER BRETTEI? W. BRETTER WASHING MACHINE Nov. 24, 1953 3Sheets-Sheet 2 Filed Aug. 12, 1952 WALTER BRETTER Nov. 24, 1953 w.BIVQETTER 2,660,045

WASHING MACHINE Filed Aug. 12, 1952 s Sheets-Sheet s WALTER BRETTETE.lNvENTofi Patented Nov. 24, 1953 UNITED s'mr TENT OFFICE WASHING MACHINE3 Claims.

This invention relates to washing machines for textile fabrics andgarments, and particularly to a machine of the type in which an agitatoris rotatably mounted in a tank for containing the washing liquid and thearticles to be washed,said agitator being driven by an electric motor orotherwise so that the washing liquid may be circulated and the articlesthoroughly washed.

It has already been proposed to provide a clothes washing machine ofthis type in which the base of the tank is apertured around a pointofiset from both horizontal axes which intersect at right angles andpass through the middle of said bottom, in which the agitator fitsclosely and co-axially within the aperture, and in which the sides ofthe tank are arranged in relation to the aforesaid point so that theylie tangential to a continuous curve traced from and around said pointand steadily increasing its distance from said point.

It has been found that with the machine described above, satisfactoryresults are only obtained if the washing load is relatively small insize and weight. If the Washing load is increased even to a practicalminimum, the articles are liable to become unduly damaged by theagitator, the upper surface of which is formed with vanes or ribs thecrests of which are flush with the aforesaid upper surface, oralternatively with a plurality of depressions.

The present invention aims at overcoming this disadvantage.

' In accordance with the invention, a Washing machine comprises an innertank for receiving Washing liquid and the articles to be washed, saidinner tank having the base thereof apertured around a point offset fromboth horizontal axes which intersect at right angles and pass throughthe centre of said bottom and having four sides arranged in relation tosaid point so that they lie tan ential to a continuous curve traced fromand around said point and steadily increasing its distance from saidpoint; deflectin members interposed between adjacent sides of the innertank; a centrifugal impeller fitting coaxially within the aperturedportion of the base of the inner tank; a prime mover for impartingrotation to the impeller; an outer tank surrounding the inner tank andmaintained in spaced relationship therefrom; port means in the wall ofthe inner tank through which washing liquid may pass to the spacebetween the inner and outer tanks to be drawn axially into the impellerand discharged radially therefrom into the interior of the inner tank toprovide a continuous circulation.

Preferably, the impeller is mounted directly on the shaft of the primemover. It has a smooth upper surface and is provided on its undersidewith a plurality of blades or vanes the inner ends of which are disposedaround a pitch circle described about the axis, and the blades maydecrease in depth as they advance towards the periphery. Preferably, theblades are inclined to the radii of the pitch circle, for example, at anangle of For receiving the impeller, the base of the inner tank may beprovided with an aperture Which, in vertical section, is of invertedfrustroconical shape, the major diameter being greater than the overalldiameter of the impeller, and the minor diameter less, and preferablycorresponding to the pitch circle around which the inner ends of theimpeller blades are disposed.

The space between the walls of the two tanks may communicate directlywith the space between the bases of the tanks, such latter space in turnleading inwards to the underside of the impeller so that Washing liquidmay be drawn axially into the impeller into the gap between the impellerboss and the inner ends of the blades.

The invention will be further described with reference to theaccompanying drawings in which:

Figure 1 is a part sectional elevation of a washing machine according tothe invention.

Figure 2 is a cross-section on the line II--II in Figure 1.

Figure 3 is a cross-section on the line III-III in Figure 1.

Figure 4 is an inverted plan view of the impeller.

Fig. 5 is an enlarged detail, partly in section, of the impeller andsurrounding parts.

Referring to the drawings, the machine comprises an inner tank I havingfour sides, 2, 3, 4 and 5 and deflecting members 6, 1, 8 and 9interposed between said sides. The base In of the tank I is apertured atI! around a point It offset from both horizontal axes I3 and M whichintersect at right angles and pass through the middle of the base Ill.The sides 2, 3, 4 and 5 are arranged in relation to the point [2 so thatthey lie tangential to a logarithmic spiral l5 evolved from the pointI2.

The aperture I! is of inverted frusto-conical shape, the major diameterbeing greater than the overall diameter of the impeller and the minordiameter less.

The impeller I6 is provided on its underside with eight blades I! theinner ends of which are disposed about a pitch circle l8 described aboutthe axis I9. The blades [1 are inclined to the radii of the pitch circleI8 at an angle of 60 and, as shown, they decrease in depth as theyadvance outwards towards the periphery. The impeller I6 is mounted onthe motor shaft with the blades II- just clear of the surface of theaperture I I.

The outer tank 2I surrounds the inner tank I and is maintained in spacedrelationship-therefrom by means of a supporting member 22 having threeupwardly-extending"legs 23'to;which the inner tank I is securedbyscrews24, and by means of additional supports22a; The supporting member22 is attached by screws 25"to a' casting 26 to which the drivingmotor2'I is bolted at 28. The outer tank 2| is bolted at 29- to thecasting 26.

The outer tank 2I is supported on a stand 3'! by means of invertedu-shaped brackets 3i welded to the base of the outer tank 2| andboltedon to a pair of angle iron brackets 39 provided on opposite sides of theinterior of the standBl.

A pump impeller 32 is mounted on the motor shaft 22 in the space 33between theunderside of the supporting member 22 and the casting 26, theinlet to said-pump being axial through the supportingv member 22. Adischarge hose 34 communicates with the space 33-and is controlled by avalve 35 operated by a handle 36.

The Walls of the inner tank 'I are apertured at 39 to permitthe-passage-of washing liquid from the inner tankinto the space .40between the inner tank-I and the-outer tank 2 I. The base-of the innertank I is formed with. sloping.;;drain grooves 38 to ensure properdrainage of washing liquid from the .interiocof the .tankcafter use.

the space .40. The valve 35 is kept closed and the motor 27 started.Liquid .is'drawnaxially into the impeller. I6.and discharged intotheinner tank I.. The impact of the discharging liquid upon the stationaryliquid in the innertank I causes circulation of the latter andeventually avortex is formed in the centreof the inner tank.

However, since the impeller I6 is mounted olf centre, adequate motion is,imparted to the :ar-

ti-cles to be washed and:

(a) Sincethere is no suction. from the delivery side in the inner tank,the articles are not forced on to the impeller.

'(b) The only moving part which the articles can touch is the smooth.upper surface :of the impeller so that no untoward damagecan occur.

(c) The force of the washing liquid discharged from the impeller willtend to keep the articles clear of the impeller.

The washing liquid passes through the ports 39 after most of its kineticenerg has been spent and the cycle is continued. When the washingoperation is completed, the valve 35 is opened and the pump. 32 emptiesthe machine through the hose 34.

I claim:

1. A washing machine comprising an inner tankforreceiving washing liquidand the articles to be washed,.,said inner tank having the base thereofapertured around a point oiTset from each of two horizontal axes whichintersect at right angles and pass through the centre of said bottomandhaving .four sides arranged in relation to said point so that theylie tangential to a continuous curve traced from and around said pointand steadily increasing its distance from said point; deflecting membersinterposed between adjacent sides of the inner tank; a centrifugalimpeller fitting co-axially within the apertured portion of the base ofthe inner tank; a prime mover for imparting rotation to the impeller; anouter'tank surrounding the inner tank and maintained in spacedrelationship therefrom; port means in the wall of the inner tankthroughwhich washing liquid may pass to the space between the inner and outertanks to be drawn axially into :the impeller and discharged radiallytherefrom into the interior of the innertank-to provide a'continuouscirculation.

2. A- washing machine; accordingto claim 1, in which theimpeller isprovided on its underside with a plurality of vanes the inner ends ofwhich are disposed around a pitch-circle-described about the axis, saidvanes'decreasing in' depthas they advance towards the periphery, and inwhich, the aperture in the base of the inner tank "within which theimpeller is receivedris, inwertical sec-' tion, of invertedfrustro-conical shape; the'major diameter being greater than theoverall'diameter of the impeller and theminor diameter less.

3. A washing machine; according to claim- 2,- in which the vanes areinclined to the radii ofthe pitch circle.

WALTER BRE'I'TER.

References Cited in'thefile of this patent UNITED STATES PATENTS NumberName Date 1,982,002 Hatch .Nov. 27, 1934 2,071,622 Gibson Feb. 23; 19372,105,094. Pearce- Jan. 11, 1938 2,482,319 Casse Sept, 20, 1949-2,'502,965 Knapp Apr. 4, 1950

